Corn Milling Process - PDF

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Description: S Not Applicable.STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT Not Applicable.BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to grain milling generally, and more particularly, to an improved differential corn milling process. 2. Description of Related Art In a conventional corn milling process, corn kernels are cleaned, tempered, and then sent to a degerminator, which attempts to remove the germ from each kernel without substantially grinding the germ. The corn particles exiting the degerminatorare separated into "tail" and "thru" streams, the former being relatively rich in endosperm and the latter being relatively rich in bran and germ. Each stream is then preferably passed through aspirators for bran removal and gravity tables to achievefurther sorting of each stream by particle density. Next, each stream is passed through a series of differential roller mills and sieves to grind and separate the corn particles within each stream to a desired size and purity. Typically, there are two series of differential roller mills, one forthe endosperm rich stream (i.e. the break rollers) and one for the germ rich stream (i.e. the germ rollers). Each series consists of successive roller mills designed to gradually reduce endosperm particle size. Each roller mill consists of a pair ofcounter-rotating rollers which rotate at different speeds and have corrugations designed to grind the endosperm particles. Typically, the germ rollers have a lower roll speed differential than the break rollers in order to reduce grinding and abrasionon the relatively fragile germ. The first roller mill in each series typically has relatively large corrugations (e.g. approximately 6 corrugations per inch) and the final roller mills in each series typically have relatively small corrugations (e.g. approximately 16-24corrugations per inch). Relatively large particles from the gravity tables go to the first break or germ rollers, respec